Visual display unit bc 110/b, 1 overview 12.2 checking the visual display unit, 1 overview – HEIDENHAIN TNC 415 (259 9x0) Service Manual User Manual
Page 78: 2 checking the visual display unit
SERVICE MANUAL TNC 415B/425
Page 73
Issue: 20.08.95
12. Visual Display Unit BC 110/B
12.1 Overview
BC 110 Id.No. 254 740 01
BC 110 B Id.No. 260 520 01
12.2 Checking the Visual Display Unit
BC 110 B, Id.No. 260 520 01
If the screen remains dark when the machine is switched on, first check the power supply (line voltage) of the
VDU. If the voltage supply is functioning properly, a square highlighted filed can be generated on the screen of
the VDU (which must be switched on) by pressing the external test button on the back side of the unit.
highlighted field
external test button
If the VDU generates this highlighted field, the PLC graphics board in the logic unit is probably defective.
If however, the VDU remains dark after the test button was pressed, the VDU is defective and must be
exchanged.